summaryrefslogtreecommitdiff
path: root/drivers/iio/temperature/tsys02d.c
blob: 9b2e56fa5fd5c5a94ff0a2efcb32ea61926d7063 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
/*
 * tsys02d.c - Support for Measurement-Specialties tsys02d temperature sensor
 *
 * Copyright (c) 2015 Measurement-Specialties
 *
 * Licensed under the GPL-2.
 *
 * (7-bit I2C slave address 0x40)
 *
 * Datasheet:
 *  http://www.meas-spec.com/downloads/Digital_Sensor_TSYS02D.pdf
 */

#include <linux/init.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/stat.h>
#include <linux/module.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

#include "../common/ms_sensors/ms_sensors_i2c.h"

#define TSYS02D_RESET				0xFE

static const int tsys02d_samp_freq[4] = { 20, 40, 70, 140 };
/* String copy of the above const for readability purpose */
static const char tsys02d_show_samp_freq[] = "20 40 70 140";

static int tsys02d_read_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *channel, int *val,
			    int *val2, long mask)
{
	int ret;
	s32 temperature;
	struct ms_ht_dev *dev_data = iio_priv(indio_dev);

	switch (mask) {
	case IIO_CHAN_INFO_PROCESSED:
		switch (channel->type) {
		case IIO_TEMP:	/* in milli °C */
			ret = ms_sensors_ht_read_temperature(dev_data,
							     &temperature);
			if (ret)
				return ret;
			*val = temperature;

			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
	case IIO_CHAN_INFO_SAMP_FREQ:
		*val = tsys02d_samp_freq[dev_data->res_index];

		return IIO_VAL_INT;
	default:
		return -EINVAL;
	}
}

static int tsys02d_write_raw(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     int val, int val2, long mask)
{
	struct ms_ht_dev *dev_data = iio_priv(indio_dev);
	int i, ret;

	switch (mask) {
	case IIO_CHAN_INFO_SAMP_FREQ:
		i = ARRAY_SIZE(tsys02d_samp_freq);
		while (i-- > 0)
			if (val == tsys02d_samp_freq[i])
				break;
		if (i < 0)
			return -EINVAL;
		mutex_lock(&dev_data->lock);
		dev_data->res_index = i;
		ret = ms_sensors_write_resolution(dev_data, i);
		mutex_unlock(&dev_data->lock);

		return ret;
	default:
		return -EINVAL;
	}
}

static const struct iio_chan_spec tsys02d_channels[] = {
	{
		.type = IIO_TEMP,
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_PROCESSED),
		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
	}
};

static ssize_t tsys02_read_battery_low(struct device *dev,
				       struct device_attribute *attr,
				       char *buf)
{
	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
	struct ms_ht_dev *dev_data = iio_priv(indio_dev);

	return ms_sensors_show_battery_low(dev_data, buf);
}

static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(tsys02d_show_samp_freq);
static IIO_DEVICE_ATTR(battery_low, S_IRUGO,
		       tsys02_read_battery_low, NULL, 0);

static struct attribute *tsys02d_attributes[] = {
	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
	&iio_dev_attr_battery_low.dev_attr.attr,
	NULL,
};

static const struct attribute_group tsys02d_attribute_group = {
	.attrs = tsys02d_attributes,
};

static const struct iio_info tsys02d_info = {
	.read_raw = tsys02d_read_raw,
	.write_raw = tsys02d_write_raw,
	.attrs = &tsys02d_attribute_group,
};

static int tsys02d_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct ms_ht_dev *dev_data;
	struct iio_dev *indio_dev;
	int ret;
	u64 serial_number;

	if (!i2c_check_functionality(client->adapter,
				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
				     I2C_FUNC_SMBUS_WRITE_BYTE |
				     I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
		dev_err(&client->dev,
			"Adapter does not support some i2c transaction\n");
		return -EOPNOTSUPP;
	}

	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data));
	if (!indio_dev)
		return -ENOMEM;

	dev_data = iio_priv(indio_dev);
	dev_data->client = client;
	dev_data->res_index = 0;
	mutex_init(&dev_data->lock);

	indio_dev->info = &tsys02d_info;
	indio_dev->name = id->name;
	indio_dev->dev.parent = &client->dev;
	indio_dev->modes = INDIO_DIRECT_MODE;
	indio_dev->channels = tsys02d_channels;
	indio_dev->num_channels = ARRAY_SIZE(tsys02d_channels);

	i2c_set_clientdata(client, indio_dev);

	ret = ms_sensors_reset(client, TSYS02D_RESET, 15000);
	if (ret)
		return ret;

	ret = ms_sensors_read_serial(client, &serial_number);
	if (ret)
		return ret;
	dev_info(&client->dev, "Serial number : %llx", serial_number);

	return devm_iio_device_register(&client->dev, indio_dev);
}

static const struct i2c_device_id tsys02d_id[] = {
	{"tsys02d", 0},
	{}
};
MODULE_DEVICE_TABLE(i2c, tsys02d_id);

static struct i2c_driver tsys02d_driver = {
	.probe = tsys02d_probe,
	.id_table = tsys02d_id,
	.driver = {
		   .name = "tsys02d",
		   },
};

module_i2c_driver(tsys02d_driver);

MODULE_DESCRIPTION("Measurement-Specialties tsys02d temperature driver");
MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>");
MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>");
MODULE_LICENSE("GPL v2");